Dr. Andrew Medeiros

Contact Information

Academic Background

W. Garfield Weston Postdoctoral Fellow, 2012-2014

PhD, York University, 2011.

MES, York University, 2005.

BSc, Hon. First Class, Brock University, 2003.

Biography

My research focuses on the use of biological and geochemical indicators to examine ecosystem responses to environmental change. My approach integrates the use of paleolimnology, which adds a temporal context, to contemporary biogeographic research on trophic system responses to disturbance. I have used this approach to model temperature warming in Arctic regions with the use of standard statistical modelling techniques in the R statistical package. This involves the development of calibration sets for determining environmental gradients using multi-variate statistics (e.g., canonical correspondence analysis), and functions for reconstructing environmental values from biological assemblages (e.g., weighted averaging partial least squares regression). My current research combines these approaches with the use of stable isotope geochemistry to examine biotic responses to coincident changes in temperature and nutrients in a hydroecological framework. My post-doctoral research to date has found significant relationships between the source and availability of nitrogen to biological communities in a warming environment; however, there remain numerous unexplained questions behind how carbon, nitrogen, methane, and organic matter interplay in Arctic environments that are warming. Understanding how these systems responded to past climatic change would answer significant questions as to how ecosystems will respond in the future.

Medeiros AS and Quinlan R. 2011. The distribution of the Chironomidae (Insecta: Diptera) along multiple environmental gradients in lakes and ponds of the eastern Canadian Arctic. Can J Fish and Aquat Sci, 68(9):1511-1527.

Medeiros, A.S. and Quinlan, R. A Chironomidae-based stratigraphic record of pronounced 20th century warming in a large, deep, Canadian Arctic lake. 18th annual symposium of the Chironomidae, Trondheim, Norway, July 4-6, 2011.

Medeiros, A.S. and Quinlan, R. The development of a Chironomid based paleo-environmental model for the eastern Canadian Arctic. Annual workshop of the Chironomidae, Finse, Norway, June 29-July 2, 2011.

Medeiros, A.S. and Quinlan, R. Shifts in the aquatic midge community of Baker Lake, Nunavut; An indicator of pronounced 20th century environmental change. 64th Canadian Conference for Fisheries Research, Toronto, ON, January 7-8, 2011.

Medeiros, A.S. and Quinlan, R. The biogeographic distribution of Chironomidae (Insecta:Diptera) from northern Manitoba to the eastern Canadian Arctic. Association of American Geographers (AAG), Annual Conference, Washington, DC, April 15, 2010.

Medeiros, A.S. and Quinlan, R. Dynamics of thermal stratification in two small Arctic lakes, Nunavut territory, Canada. Canadian Hydrological Union, York University, October 15, 2009